


As Nature Intends

by LittleSpacePrince



Series: Tale Teller's Daily Writing Challenge [6]
Category: Marvel Cinematic Universe, The Avengers (Marvel Movies)
Genre: Alpha Tony, Alpha Tony Stark, Alpha/Beta/Omega Dynamics, Alpha/Omega, Fluff and Smut, I liked this one I kinda wanna write a sequel, Impregnation, M/M, Mating Cycles/In Heat, Mpreg, Omega Bruce, Omega Bruce Banner, Omega Verse, Plot What Plot/Porn Without Plot, Shameless Smut, Smut, well just a little plot
Language: English
Status: Completed
Published: 2018-02-07
Updated: 2018-02-07
Packaged: 2019-03-15 02:35:20
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,085
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13603749
Author URL: https://archiveofourown.org/users/LittleSpacePrince/pseuds/LittleSpacePrince
Summary: Prompt:Write your character into your favorite tropeIn which Bruce is in heat.





	As Nature Intends

**Author's Note:**

> A/B/O is a kink trope and thus it counts, fight me.

Bruce always did hate waking up like this.

His clothes clung uncomfortably to his body as the sweat began to bead across his flesh, skin flushed bright pink as he tossed restlessly in the bed. Once every month was getting frustrating, far worse than what it had once been, or at least what he could remember of his previous experiences. He’d been on suppressants for so long that he could hardly remember what it had felt like before. Uncomfortable, certainly, but never intolerable. But now, his body felt like it was going through hell. They seemed to be getting worse as he aged, body hardly able to keep up with the stress of it anymore. Part of him wished he'd just stayed on the suppressants, avoided this mess altogether, but eventually, he figured it would be worth it. Or, he hoped, at least.

It had taken years to come to this point, years that he feared they had wasted, years that may have been the closing to his window of opportunity. After all, they had gone through three heats and Bruce still hadn’t conceived. Still, perhaps the fourth time would be the charm. It didn’t quite feel promising, and was beginning to seem more and more like unnecessary torture, but he still tried. There was so much that he had wanted in life, before the Hulk had come around. Tony had vowed to give him that. But sometimes, the things that he wanted were not so easily acquired.

He tugged his t-shirt over his head before tossing it into the corner, stripping down to nothing more than a near-soiled pair of boxers, leaking with slick. He figured that he should've stripped those too, surrendered himself to the hollow ache between his thighs, but it would've been useless. It was an ache that only his alpha could soothe, a need only he could satiate. Fingers and toys only ever whet his appetite, driving him deeper and deeper into his need. No. Better just to wait. 

Bruce leaned across the bed to grab his phone, quickly pulling up Tony’s contact and pressing ‘call.’ On any given day, Tony probably wouldn't have even picked up, too engrossed in his work to bother with a phone call. But around this time of month, he was faithful to picking up the phone every time it rang, always at the ready to come running at any need. And, just like he knew he would, it took a ring and a half before the familiar voice came across the other end of the line. 

“Yeah?” Tony inquired expectantly. They had been waiting for the right timing, waiting for his heat to start for three days, every minute passing more anxious than the next. 

“I started. I'm in heat.” Bruce muttered, running a hand down his face, pinching the space between his brows. 

The line went dead without another word, and Bruce could immediately hear the pounding of footsteps from downstairs as his alpha broke into a sprint, running to his omega’s aid. Always dramatic, never wasting a second in these moments. He’d been like this since their first heat together, determined to fulfill his every need as soon as he needed it. 

Bruce smiled to himself, kicking his boxers off into the floor and scooting himself back against the headboard, preparing himself for the certain ambush that was to come. Legs parted slightly, just far enough apart for Tony to catch a glimpse of what was to come. Body leaned back, receptive to whatever his alpha had to give him. Bruce never would have been so scandalous outside of heat, always preferring modesty until the heat of the moment, always preferring to let Tony strip him of his clothes and take the lead. But under the haze of his heat, he could hardly help himself, desperate for Tony’s approval, desperate for his lust. Like heaven spread out across silk sheets.

The door flung open, Tony emerging with messy hair and eyes blown wide. He kicked the door shut behind him, stripping himself of any clothes the moment he walked through the doorway. At the speed of light, Tony’s lips were claiming his, fingers pinning him down to the mattress beneath them, cock hard and leaking against the omega’s hipbone.

Eagerly, Bruce’s body began to react, a fresh bout of slick gushing from his hole and onto the sheets below them. His legs wrapped almost instinctively around Tony’s waist, pulling him closer and refusing to let him pull away. Bruce decided then that Tony wasn’t allowed to pull away until he had been sufficiently fucked and knotted and filled, until satiation came at the end of his heat. Until that moment came, Bruce held him close, ankles locked at the small of his back, fingers laced through hair, lips moving in unspoken harmony, cocks rubbing and grinding against bare flesh in some desperate need for friction.

“Need you inside me.” Bruce whimpered, the pain between his legs growing more and more demanding, more and more urgent as the seconds of this torturous little dance ticked on. 

Tony let out a possessive growl as he let his fingers slip between them, two fingers probing at his rim, gently pressing against the taut ring of muscle, feeling it give beneath his touch. Greedily, Bruce’s hole contracted around his fingers as they pushed inside, the tight, velvety heat stretching to accommodate him. Tony suckled hard against his neck, leaving lines of purple bruises, making damn certain that Bruce was marked for days after this. He savored each moan and whimper as he curled his fingers and rubbed, pressing incessantly against the sensitive little nub until the omega was writhing and squirming beneath him. Bruce was dripping wet, hole hungrily taking in each finger, hardly needing any preparation at all. 

“Christ, Bruce, you're soaking wet for me.” Tony breathed, withdrawing his fingers and wrapping them around his cock, giving himself a few cursory pumps as he lined himself up with the omega’s twitching rim. 

_“Please.”_ Bruce whined, wriggling beneath him, sick of the foreplay. He needed to take his alpha’s cock, needed to feel the knot straining at his rim, needed to feel the gush of his seed filling his womb. 

Any other day, Tony would've kept him going, would’ve wound him up a bit more, teased him just long enough to hear him beg for it. But this time, things were a bit too urgent for so much foreplay. His eyes glanced down between them, keeping focused on the beautiful obscenity that lie beneath him. Bruce was practically drenched in his own slick from the waist down. The ruddy head of his cock leaked with pre-cum, twitching hard against his belly. He let out a small moan, vision blurring as his cock pushed into his leaking hole, sheathing himself deep inside. 

Bruce let out a cry at the intrusion, curling himself tight around the alpha, not daring to let him go. There was relief as Tony began to thrust, the pain melting into pleasure in this symphony of sensation. The alpha’s cock brushing against his prostate until he was damn near screaming, probing his cervix with each thrust, as if he was preparing the omega to take his seed. Tony’s belly rubbed hard against Bruce’s cock, the friction being almost too much to bear, only a few seconds in and already nearing his climax. 

“You're gonna wake up everyone else if you keep moaning like that. Everyone's gonna know you're in heat. Everyone's gonna know that you're getting knotted and bred.” Tony whispered as he set a more vigorous pace in an attempt to satiate his needs. 

Bruce let out a wrecked whine, burying his face into the crook of Tony’s neck. The other Avengers had known what he was for awhile now, much to the shock of a few of them. Most had assumed him to be a beta, or even an alpha, because how could the incredible Hulk be an omega, of all things? And after he'd gone off of his suppressants and began going into heat, he assumed that many of them already knew what they were trying to do. And yet, there was something incredibly scandalous about being overheard in the throes of his heat. 

“You like that, don't you?” Tony teased, nibbling at his earlobe, hot breath against his neck. “You like the idea of everyone knowing whose omega you are.” 

Bruce wanted to respond, wanted to reply with some snarky comment in return, but his brain was overridden with hormones and sex, unable to think straight enough to let out anything other than a small cry as fingernails raked down the alpha’s back. _Jesus,_ he was pitiful. 

“I can't wait to watch your belly swell with my pups. Then everyone’s gonna know exactly what you've been doing. Everyone’s gonna know about how you went into heat and couldn't keep your legs closed.” Tony huffed, hands pinning Bruce’s wrists above his head. Bruce was hardly the submissive type outside of his heat, but in the throes of need and lust and breeding, he tended to surrender himself over to Tony, let the alpha have his way, so long as he came out of it knotted, bred, and pregnant. His voice hushed to a whisper as he leaned in close. “Tell me what you want.” 

Bruce could hardly find the words to speak, but figured it better not to disobey his alpha. Toes curling tight and brain fogged with his most primal urges, he opened his mouth, just barely finding the words. 

“Want you to seed me. Want you to… Want you to put a baby in me.” He whimpered, eyes shut tight. He knew what he must've sounded like, some whore omega, begging to be bred, succumbing to his heat. But he didn't care. He didn't have the capacity to care. He found himself too consumed by his own need to care. “Want you to come inside me. Want you to knot me.” 

Tony couldn't help but smirk, the sound of his begging omega enough to give anyone an ego boost. His hips picked up speed, more pointed, more purposeful, until Bruce was practically screaming beneath him, head thrown back in ecstasy. The sight alone could've pushed him over, could've forced him to knot right then and there. But instead, he pushed harder, determined to come with his omega. Besides, during an omega’s orgasm, the cervix tended to spasm, contracting and dilating, furthering the absorption of the alpha’s semen. Or, at least, that was what he'd read online. 

“Gonna fill you up. Gonna make your belly swell with my litter.” Tony whispered, drawing a desperate whine from Bruce’s throat, back arching sharply as he squirmed beneath him. “Is that what you want? You want me to breed you, don't you?” 

And with that, Bruce was a goner. Hot, watery semen came spurting between them as he met his climax, crying out as he orgasmed. As his hole began to contract hard around Tony’s cock, and within seconds he could feel the teasing of his knot at his rim before it finally caught and Tony’s orgasm followed suit, the wet gush of warmth filling him, spreading through the pit of his belly as he slowly came back down to earth. 

“I love you.” Bruce mumbled sleepily, savoring the feeling of fullness, the feeling of warmth between his legs, spreading throughout his body. 

“I love you too. Christ, how'd I get so lucky?” Tony murmured in all earnest, counting himself lucky as the omega beneath him began to purr softly. Just a subtle vibration, more felt than heard, but still undeniably there. 

Something felt different than the other two times. He couldn't quite place it, but there was something stirring within him, almost like he could feel the sperm meeting his egg, almost like he could feel his own fertilization as it took place. An odd tingling in the pit of his belly, a warm sensation spreading through him as he allowed nature to take its course, allowing the seed to take. He buried his face into Tony’s neck, inhaling his scent, settling into his alpha as they lay knotted. 

“This is gonna be it.” Bruce murmured as he traced circles into Tony’s chest, running offer the marred scar where the arc reactor had one been. “I can feel it. This is the one that's gonna take.” 

Tony pressed his lips against his omega’s curls, fingers tracing the outline of him, and smiled.

**Author's Note:**

> THE A/B/O KING IS BACK, BITCHES


End file.
